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Introduction:International reports suggest there have been prehospital delays for time-sensitive emergencies like stroke and TIA during the COVID-19 pandemic. The aim was to investigate the impact of the COVID-19 pandemic on ambulance times and emergency call volume for adults with suspected stroke and TIA in Ireland.Method:We conducted a retrospective cohort study of patients ≥ 18 years with suspected stroke/TIA, based on data from the National Ambulance Service. We included all cases assigned code 28 (suspected stroke/TIA) by the emergency call-taker, from 2018-2021. We compared ambulance times and emergency call volume by week, the four COVID-19 waves (defined by the Health Protection Surveillance Centre) and annually. The COVID-19 period was from March 1, 2020 - December 19, 2021 and the pre-COVID-19 period January 1, 2018 - February 29, 2020. Continuous variables were compared with t-tests and categorical variables with Pearson’s χ2 tests.Results:40,012 cases were included: 20,281 in the pre-COVID-19 period and 19,731 in the COVID-19 period. Mean patient age significantly decreased between the two periods, from 71 years (±16.5) to 69.8 years (±17.1); p<0.001. Mean ambulance response time increased between the two periods from 17 minutes 31 seconds to 18 minutes 59 seconds (p<0.001). The number of cases with symptom onset to emergency call time of >4 hours significantly increased from 5,581 to 6,060 during the COVID-19 period (p<0.001). Mean calls/day increased from 25.1/day to 30.1/day during the COVID-19 period.Conclusion:Early findings from the study suggest an increase in call volume for stroke/TIA between the COVID-19 and pre-COVID-19 periods. An increase in response times during the same periods was also found. We concluded that longer symptom-to-call times indicate a change in healthcare-seeking behavior. Sustaining high levels of compliance with stroke code protocols is crucial during healthcare crises. Future research will involve further analysis including controlling for confounders.

Northern Ireland has been subject to significant maritime influences throughout its known 9,000-year human history. In 1997, the University of Ulster, in partnership with the Environment and Heritage Service, embarked on a program of seabed mapping in an attempt to record the submerged and buried archaeological resources. To date, the geophysical research program has imaged about 80 19th- and 20th-century wrecks and about 100 targets of further “archaeological potential.” One method of integrating the results of geophysical surveys into the Maritime Sites and Monuments Record (SMR) is the use of the classification scheme CEBESSt, an alphanumeric wreck-site classification scheme based upon six site-specific variables: Composition of hull, Energy of wreck environment, Burial, Exposure, Structural integrity, and Substrate type, with t corresponding to time (the year of wrecking, if known). The classification is designed for use within a database scheme that allows for interrogation through character recognition and pattern matching.

Recent marine survey programs have generated a GIS (geographic information system) distribution of historic wreck sites around the coast of Northern Ireland. These data lead to an understanding of the nature and extent of submerged cultural resources and provide statistical information on the spatial and temporal distribution of historic wrecks, allowing for the reconstruction of past maritime activity. This is important baseline data used for the production of integrated research and management plans for the protection of the resources.

Rathlin Island, off the north coast of Ireland, has a history of settlement and seafaring from the Late Mesolithic period to the present day. The maritime Sites and Monuments Record (SMR) for Rathlin indicates many wrecking incidents. In 1999, a reconnaissance side‐scan sonar survey confirmed the presence of 46 targets of possible archaeological potential around Rathlin Island. Thirteen of these anomalies were positively identified as shipwrecks. Of the remaining 33 targets, nine were dived on in order to ground‐truth the geophysical data. A successful and rapid methodology of ground‐truthing side‐scan sonar data for archaeological purposes was developed. The results confirmed the presence of a Danforth Anchor at one site, while the remaining anomalies were identified as geological features. The results from the side‐scan survey and diver‐truthing exercise enhanced the existing maritime SMR. © 2002 Wiley Periodicals, Inc.

Northern Ireland has been subject to significant maritime influences throughout its 9000‐year known human history. In 1997 the University of Ulster in partnership with the Environment and Heritage Service (DOE, NI) embarked on a programme of seabed mapping in an attempt to record the submerged and buried archaeological resource using a suite of geophysical equipment including a side‐scan sonar, a Chirp sub‐bottom profiler and a proton precession magnetometer. The geophysical research programme has successfully imaged 80 19th‐ and 20th‐century wrecks, and 20 targets of further archaeological potential. These data will aid the production of wreck‐prediction indices for the coastline of Northern Ireland based on site formation processes and site stability. This information will make valuable additions to both Sites and Monuments Records and to the shipwreck database currently under consideration at the University of Ulster.

Chirp sub-bottom profilers produce high-resolution images of the near-surface. An attribute of the sea-bed reflection in chirp data are fluctuations in polarity between adjacent traces. Two models are proposed and presented to explain this: the first incorporates changes in an acoustic impedance gradient at the sea bed; the second uses changes in the thickness of the uppermost sediment layer. Mixing of adjacent traces produces a consistent polarity for the sea-bed reflector. Reflection coefficients are calculated, using amplitude information derived from single-traces, and polarity information from trace mixing, with application to a marine archaeological case study. The reflection coefficient calculated for the top of a buried 18th century wooden wreck is -0.26.